/***
 * ASM XML Adapter
 * Copyright (c) 2004-2011, Eugene Kuleshov
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the copyright holders nor the names of its
 *    contributors may be used to endorse or promote products derived from
 *    this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 */
package org.objectweb.asm.xml;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;

import org.objectweb.asm.AnnotationVisitor;
import org.objectweb.asm.ClassVisitor;
import org.objectweb.asm.FieldVisitor;
import org.objectweb.asm.Handle;
import org.objectweb.asm.Label;
import org.objectweb.asm.MethodVisitor;
import org.objectweb.asm.ModuleVisitor;
import org.objectweb.asm.Opcodes;
import org.objectweb.asm.Type;
import org.objectweb.asm.TypePath;
import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.DefaultHandler;

/**
 * A {@link org.xml.sax.ContentHandler ContentHandler} that transforms XML
 * document into Java class file. This class can be feeded by any kind of SAX
 * 2.0 event producers, e.g. XML parser, XSLT or XPath engines, or custom code.
 * 
 * @see org.objectweb.asm.xml.SAXClassAdapter
 * @see org.objectweb.asm.xml.Processor
 * 
 * @author Eugene Kuleshov
 */
public class ASMContentHandler extends DefaultHandler implements Opcodes {

  /**
   * Stack of the intermediate processing contexts.
   */
  private final ArrayList<Object> stack = new ArrayList<Object>();

  /**
   * Complete name of the current element.
   */
  String match = "";

  /**
   * Current instance of the {@link ClassVisitor ClassVisitor} used to visit
   * classfile bytecode.
   */
  protected ClassVisitor cv;

  /**
   * Map of the active {@link Label Label} instances for current method.
   */
  protected Map<Object, Label> labels;

  private static final String BASE = "class";

  private final RuleSet RULES = new RuleSet();
  {
    RULES.add(BASE, new ClassRule());
    RULES.add(BASE + "/interfaces/interface", new InterfaceRule());
    RULES.add(BASE + "/interfaces", new InterfacesRule());
    RULES.add(BASE + "/outerclass", new OuterClassRule());
    RULES.add(BASE + "/innerclass", new InnerClassRule());
    RULES.add(BASE + "/source", new SourceRule());

    ModuleRule moduleRule = new ModuleRule();
    RULES.add(BASE + "/module", moduleRule);
    RULES.add(BASE + "/module/main-class", moduleRule);
    RULES.add(BASE + "/module/target", moduleRule);
    RULES.add(BASE + "/module/packages", moduleRule);
    RULES.add(BASE + "/module/requires", moduleRule);
    RULES.add(BASE + "/module/exports", moduleRule);
    RULES.add(BASE + "/module/exports/to", moduleRule);
    RULES.add(BASE + "/module/uses", moduleRule);
    RULES.add(BASE + "/module/provides", moduleRule);

    RULES.add(BASE + "/field", new FieldRule());

    RULES.add(BASE + "/method", new MethodRule());
    RULES.add(BASE + "/method/exceptions/exception", new ExceptionRule());
    RULES.add(BASE + "/method/exceptions", new ExceptionsRule());

    RULES.add(BASE + "/method/parameter", new MethodParameterRule());
    RULES.add(BASE + "/method/annotationDefault", new AnnotationDefaultRule());

    RULES.add(BASE + "/method/code/*", new OpcodesRule()); // opcodes

    RULES.add(BASE + "/method/code/frame", new FrameRule());
    RULES.add(BASE + "/method/code/frame/local", new FrameTypeRule());
    RULES.add(BASE + "/method/code/frame/stack", new FrameTypeRule());

    RULES.add(BASE + "/method/code/TABLESWITCH", new TableSwitchRule());
    RULES.add(BASE + "/method/code/TABLESWITCH/label", new TableSwitchLabelRule());
    RULES.add(BASE + "/method/code/LOOKUPSWITCH", new LookupSwitchRule());
    RULES.add(BASE + "/method/code/LOOKUPSWITCH/label", new LookupSwitchLabelRule());

    RULES.add(BASE + "/method/code/INVOKEDYNAMIC", new InvokeDynamicRule());
    RULES.add(BASE + "/method/code/INVOKEDYNAMIC/bsmArg", new InvokeDynamicBsmArgumentsRule());

    RULES.add(BASE + "/method/code/Label", new LabelRule());
    RULES.add(BASE + "/method/code/TryCatch", new TryCatchRule());
    RULES.add(BASE + "/method/code/LineNumber", new LineNumberRule());
    RULES.add(BASE + "/method/code/LocalVar", new LocalVarRule());
    RULES.add(BASE + "/method/code/Max", new MaxRule());

    RULES.add("*/annotation", new AnnotationRule());
    RULES.add("*/typeAnnotation", new TypeAnnotationRule());
    RULES.add("*/parameterAnnotation", new AnnotationParameterRule());
    RULES.add("*/insnAnnotation", new InsnAnnotationRule());
    RULES.add("*/tryCatchAnnotation", new TryCatchAnnotationRule());
    RULES.add("*/localVariableAnnotation", new LocalVariableAnnotationRule());
    RULES.add("*/annotationValue", new AnnotationValueRule());
    RULES.add("*/annotationValueAnnotation", new AnnotationValueAnnotationRule());
    RULES.add("*/annotationValueEnum", new AnnotationValueEnumRule());
    RULES.add("*/annotationValueArray", new AnnotationValueArrayRule());
  }

  private static interface OpcodeGroup {
    public static final int INSN = 0;
    public static final int INSN_INT = 1;
    public static final int INSN_VAR = 2;
    public static final int INSN_TYPE = 3;
    public static final int INSN_FIELD = 4;
    public static final int INSN_METHOD = 5;
    public static final int INSN_JUMP = 6;
    public static final int INSN_LDC = 7;
    public static final int INSN_IINC = 8;
    public static final int INSN_MULTIANEWARRAY = 9;
  }

  /**
   * Map of the opcode names to opcode and opcode group
   */
  static final HashMap<String, Opcode> OPCODES = new HashMap<String, Opcode>();
  static {
    addOpcode("NOP", NOP, OpcodeGroup.INSN);
    addOpcode("ACONST_NULL", ACONST_NULL, OpcodeGroup.INSN);
    addOpcode("ICONST_M1", ICONST_M1, OpcodeGroup.INSN);
    addOpcode("ICONST_0", ICONST_0, OpcodeGroup.INSN);
    addOpcode("ICONST_1", ICONST_1, OpcodeGroup.INSN);
    addOpcode("ICONST_2", ICONST_2, OpcodeGroup.INSN);
    addOpcode("ICONST_3", ICONST_3, OpcodeGroup.INSN);
    addOpcode("ICONST_4", ICONST_4, OpcodeGroup.INSN);
    addOpcode("ICONST_5", ICONST_5, OpcodeGroup.INSN);
    addOpcode("LCONST_0", LCONST_0, OpcodeGroup.INSN);
    addOpcode("LCONST_1", LCONST_1, OpcodeGroup.INSN);
    addOpcode("FCONST_0", FCONST_0, OpcodeGroup.INSN);
    addOpcode("FCONST_1", FCONST_1, OpcodeGroup.INSN);
    addOpcode("FCONST_2", FCONST_2, OpcodeGroup.INSN);
    addOpcode("DCONST_0", DCONST_0, OpcodeGroup.INSN);
    addOpcode("DCONST_1", DCONST_1, OpcodeGroup.INSN);
    addOpcode("BIPUSH", BIPUSH, OpcodeGroup.INSN_INT);
    addOpcode("SIPUSH", SIPUSH, OpcodeGroup.INSN_INT);
    addOpcode("LDC", LDC, OpcodeGroup.INSN_LDC);
    addOpcode("ILOAD", ILOAD, OpcodeGroup.INSN_VAR);
    addOpcode("LLOAD", LLOAD, OpcodeGroup.INSN_VAR);
    addOpcode("FLOAD", FLOAD, OpcodeGroup.INSN_VAR);
    addOpcode("DLOAD", DLOAD, OpcodeGroup.INSN_VAR);
    addOpcode("ALOAD", ALOAD, OpcodeGroup.INSN_VAR);
    addOpcode("IALOAD", IALOAD, OpcodeGroup.INSN);
    addOpcode("LALOAD", LALOAD, OpcodeGroup.INSN);
    addOpcode("FALOAD", FALOAD, OpcodeGroup.INSN);
    addOpcode("DALOAD", DALOAD, OpcodeGroup.INSN);
    addOpcode("AALOAD", AALOAD, OpcodeGroup.INSN);
    addOpcode("BALOAD", BALOAD, OpcodeGroup.INSN);
    addOpcode("CALOAD", CALOAD, OpcodeGroup.INSN);
    addOpcode("SALOAD", SALOAD, OpcodeGroup.INSN);
    addOpcode("ISTORE", ISTORE, OpcodeGroup.INSN_VAR);
    addOpcode("LSTORE", LSTORE, OpcodeGroup.INSN_VAR);
    addOpcode("FSTORE", FSTORE, OpcodeGroup.INSN_VAR);
    addOpcode("DSTORE", DSTORE, OpcodeGroup.INSN_VAR);
    addOpcode("ASTORE", ASTORE, OpcodeGroup.INSN_VAR);
    addOpcode("IASTORE", IASTORE, OpcodeGroup.INSN);
    addOpcode("LASTORE", LASTORE, OpcodeGroup.INSN);
    addOpcode("FASTORE", FASTORE, OpcodeGroup.INSN);
    addOpcode("DASTORE", DASTORE, OpcodeGroup.INSN);
    addOpcode("AASTORE", AASTORE, OpcodeGroup.INSN);
    addOpcode("BASTORE", BASTORE, OpcodeGroup.INSN);
    addOpcode("CASTORE", CASTORE, OpcodeGroup.INSN);
    addOpcode("SASTORE", SASTORE, OpcodeGroup.INSN);
    addOpcode("POP", POP, OpcodeGroup.INSN);
    addOpcode("POP2", POP2, OpcodeGroup.INSN);
    addOpcode("DUP", DUP, OpcodeGroup.INSN);
    addOpcode("DUP_X1", DUP_X1, OpcodeGroup.INSN);
    addOpcode("DUP_X2", DUP_X2, OpcodeGroup.INSN);
    addOpcode("DUP2", DUP2, OpcodeGroup.INSN);
    addOpcode("DUP2_X1", DUP2_X1, OpcodeGroup.INSN);
    addOpcode("DUP2_X2", DUP2_X2, OpcodeGroup.INSN);
    addOpcode("SWAP", SWAP, OpcodeGroup.INSN);
    addOpcode("IADD", IADD, OpcodeGroup.INSN);
    addOpcode("LADD", LADD, OpcodeGroup.INSN);
    addOpcode("FADD", FADD, OpcodeGroup.INSN);
    addOpcode("DADD", DADD, OpcodeGroup.INSN);
    addOpcode("ISUB", ISUB, OpcodeGroup.INSN);
    addOpcode("LSUB", LSUB, OpcodeGroup.INSN);
    addOpcode("FSUB", FSUB, OpcodeGroup.INSN);
    addOpcode("DSUB", DSUB, OpcodeGroup.INSN);
    addOpcode("IMUL", IMUL, OpcodeGroup.INSN);
    addOpcode("LMUL", LMUL, OpcodeGroup.INSN);
    addOpcode("FMUL", FMUL, OpcodeGroup.INSN);
    addOpcode("DMUL", DMUL, OpcodeGroup.INSN);
    addOpcode("IDIV", IDIV, OpcodeGroup.INSN);
    addOpcode("LDIV", LDIV, OpcodeGroup.INSN);
    addOpcode("FDIV", FDIV, OpcodeGroup.INSN);
    addOpcode("DDIV", DDIV, OpcodeGroup.INSN);
    addOpcode("IREM", IREM, OpcodeGroup.INSN);
    addOpcode("LREM", LREM, OpcodeGroup.INSN);
    addOpcode("FREM", FREM, OpcodeGroup.INSN);
    addOpcode("DREM", DREM, OpcodeGroup.INSN);
    addOpcode("INEG", INEG, OpcodeGroup.INSN);
    addOpcode("LNEG", LNEG, OpcodeGroup.INSN);
    addOpcode("FNEG", FNEG, OpcodeGroup.INSN);
    addOpcode("DNEG", DNEG, OpcodeGroup.INSN);
    addOpcode("ISHL", ISHL, OpcodeGroup.INSN);
    addOpcode("LSHL", LSHL, OpcodeGroup.INSN);
    addOpcode("ISHR", ISHR, OpcodeGroup.INSN);
    addOpcode("LSHR", LSHR, OpcodeGroup.INSN);
    addOpcode("IUSHR", IUSHR, OpcodeGroup.INSN);
    addOpcode("LUSHR", LUSHR, OpcodeGroup.INSN);
    addOpcode("IAND", IAND, OpcodeGroup.INSN);
    addOpcode("LAND", LAND, OpcodeGroup.INSN);
    addOpcode("IOR", IOR, OpcodeGroup.INSN);
    addOpcode("LOR", LOR, OpcodeGroup.INSN);
    addOpcode("IXOR", IXOR, OpcodeGroup.INSN);
    addOpcode("LXOR", LXOR, OpcodeGroup.INSN);
    addOpcode("IINC", IINC, OpcodeGroup.INSN_IINC);
    addOpcode("I2L", I2L, OpcodeGroup.INSN);
    addOpcode("I2F", I2F, OpcodeGroup.INSN);
    addOpcode("I2D", I2D, OpcodeGroup.INSN);
    addOpcode("L2I", L2I, OpcodeGroup.INSN);
    addOpcode("L2F", L2F, OpcodeGroup.INSN);
    addOpcode("L2D", L2D, OpcodeGroup.INSN);
    addOpcode("F2I", F2I, OpcodeGroup.INSN);
    addOpcode("F2L", F2L, OpcodeGroup.INSN);
    addOpcode("F2D", F2D, OpcodeGroup.INSN);
    addOpcode("D2I", D2I, OpcodeGroup.INSN);
    addOpcode("D2L", D2L, OpcodeGroup.INSN);
    addOpcode("D2F", D2F, OpcodeGroup.INSN);
    addOpcode("I2B", I2B, OpcodeGroup.INSN);
    addOpcode("I2C", I2C, OpcodeGroup.INSN);
    addOpcode("I2S", I2S, OpcodeGroup.INSN);
    addOpcode("LCMP", LCMP, OpcodeGroup.INSN);
    addOpcode("FCMPL", FCMPL, OpcodeGroup.INSN);
    addOpcode("FCMPG", FCMPG, OpcodeGroup.INSN);
    addOpcode("DCMPL", DCMPL, OpcodeGroup.INSN);
    addOpcode("DCMPG", DCMPG, OpcodeGroup.INSN);
    addOpcode("IFEQ", IFEQ, OpcodeGroup.INSN_JUMP);
    addOpcode("IFNE", IFNE, OpcodeGroup.INSN_JUMP);
    addOpcode("IFLT", IFLT, OpcodeGroup.INSN_JUMP);
    addOpcode("IFGE", IFGE, OpcodeGroup.INSN_JUMP);
    addOpcode("IFGT", IFGT, OpcodeGroup.INSN_JUMP);
    addOpcode("IFLE", IFLE, OpcodeGroup.INSN_JUMP);
    addOpcode("IF_ICMPEQ", IF_ICMPEQ, OpcodeGroup.INSN_JUMP);
    addOpcode("IF_ICMPNE", IF_ICMPNE, OpcodeGroup.INSN_JUMP);
    addOpcode("IF_ICMPLT", IF_ICMPLT, OpcodeGroup.INSN_JUMP);
    addOpcode("IF_ICMPGE", IF_ICMPGE, OpcodeGroup.INSN_JUMP);
    addOpcode("IF_ICMPGT", IF_ICMPGT, OpcodeGroup.INSN_JUMP);
    addOpcode("IF_ICMPLE", IF_ICMPLE, OpcodeGroup.INSN_JUMP);
    addOpcode("IF_ACMPEQ", IF_ACMPEQ, OpcodeGroup.INSN_JUMP);
    addOpcode("IF_ACMPNE", IF_ACMPNE, OpcodeGroup.INSN_JUMP);
    addOpcode("GOTO", GOTO, OpcodeGroup.INSN_JUMP);
    addOpcode("JSR", JSR, OpcodeGroup.INSN_JUMP);
    addOpcode("RET", RET, OpcodeGroup.INSN_VAR);
    addOpcode("IRETURN", IRETURN, OpcodeGroup.INSN);
    addOpcode("LRETURN", LRETURN, OpcodeGroup.INSN);
    addOpcode("FRETURN", FRETURN, OpcodeGroup.INSN);
    addOpcode("DRETURN", DRETURN, OpcodeGroup.INSN);
    addOpcode("ARETURN", ARETURN, OpcodeGroup.INSN);
    addOpcode("RETURN", RETURN, OpcodeGroup.INSN);
    addOpcode("GETSTATIC", GETSTATIC, OpcodeGroup.INSN_FIELD);
    addOpcode("PUTSTATIC", PUTSTATIC, OpcodeGroup.INSN_FIELD);
    addOpcode("GETFIELD", GETFIELD, OpcodeGroup.INSN_FIELD);
    addOpcode("PUTFIELD", PUTFIELD, OpcodeGroup.INSN_FIELD);
    addOpcode("INVOKEVIRTUAL", INVOKEVIRTUAL, OpcodeGroup.INSN_METHOD);
    addOpcode("INVOKESPECIAL", INVOKESPECIAL, OpcodeGroup.INSN_METHOD);
    addOpcode("INVOKESTATIC", INVOKESTATIC, OpcodeGroup.INSN_METHOD);
    addOpcode("INVOKEINTERFACE", INVOKEINTERFACE, OpcodeGroup.INSN_METHOD);
    addOpcode("NEW", NEW, OpcodeGroup.INSN_TYPE);
    addOpcode("NEWARRAY", NEWARRAY, OpcodeGroup.INSN_INT);
    addOpcode("ANEWARRAY", ANEWARRAY, OpcodeGroup.INSN_TYPE);
    addOpcode("ARRAYLENGTH", ARRAYLENGTH, OpcodeGroup.INSN);
    addOpcode("ATHROW", ATHROW, OpcodeGroup.INSN);
    addOpcode("CHECKCAST", CHECKCAST, OpcodeGroup.INSN_TYPE);
    addOpcode("INSTANCEOF", INSTANCEOF, OpcodeGroup.INSN_TYPE);
    addOpcode("MONITORENTER", MONITORENTER, OpcodeGroup.INSN);
    addOpcode("MONITOREXIT", MONITOREXIT, OpcodeGroup.INSN);
    addOpcode("MULTIANEWARRAY", MULTIANEWARRAY, OpcodeGroup.INSN_MULTIANEWARRAY);
    addOpcode("IFNULL", IFNULL, OpcodeGroup.INSN_JUMP);
    addOpcode("IFNONNULL", IFNONNULL, OpcodeGroup.INSN_JUMP);
  }

  private static void addOpcode(String operStr, int oper, int group) {
    OPCODES.put(operStr, new Opcode(oper, group));
  }

  static final HashMap<String, Integer> TYPES = new HashMap<String, Integer>();
  static {
    String[] types = SAXCodeAdapter.TYPES;
    for (int i = 0; i < types.length; i++) {
      TYPES.put(types[i], i);
    }
  }

  /**
   * Constructs a new {@link ASMContentHandler ASMContentHandler} object.
   * 
   * @param cv
   *          class visitor that will be called to reconstruct the classfile
   *          using the XML stream.
   */
  public ASMContentHandler(final ClassVisitor cv) {
    this.cv = cv;
  }

  /**
   * Process notification of the start of an XML element being reached.
   * 
   * @param ns
   *          - The Namespace URI, or the empty string if the element has no
   *          Namespace URI or if Namespace processing is not being performed.
   * @param lName
   *          - The local name (without prefix), or the empty string if
   *          Namespace processing is not being performed.
   * @param qName
   *          - The qualified name (with prefix), or the empty string if
   *          qualified names are not available.
   * @param list
   *          - The attributes attached to the element. If there are no
   *          attributes, it shall be an empty Attributes object.
   * @exception SAXException
   *              if a parsing error is to be reported
   */
  @Override
  public final void startElement(final String ns, final String lName, final String qName, final Attributes list) throws SAXException {
    // the actual element name is either in lName or qName, depending
    // on whether the parser is namespace aware
    String name = lName == null || lName.length() == 0 ? qName : lName;

    // Compute the current matching rule
    StringBuilder sb = new StringBuilder(match);
    if (match.length() > 0) {
      sb.append('/');
    }
    sb.append(name);
    match = sb.toString();

    // Fire "begin" events for all relevant rules
    Rule r = (Rule) RULES.match(match);
    if (r != null) {
      r.begin(name, list);
    }
  }

  /**
   * Process notification of the end of an XML element being reached.
   * 
   * @param ns
   *          - The Namespace URI, or the empty string if the element has no
   *          Namespace URI or if Namespace processing is not being performed.
   * @param lName
   *          - The local name (without prefix), or the empty string if
   *          Namespace processing is not being performed.
   * @param qName
   *          - The qualified XML 1.0 name (with prefix), or the empty string if
   *          qualified names are not available.
   * 
   * @exception SAXException
   *              if a parsing error is to be reported
   */
  @Override
  public final void endElement(final String ns, final String lName, final String qName) throws SAXException {
    // the actual element name is either in lName or qName, depending
    // on whether the parser is namespace aware
    String name = lName == null || lName.length() == 0 ? qName : lName;

    // Fire "end" events for all relevant rules in reverse order
    Rule r = (Rule) RULES.match(match);
    if (r != null) {
      r.end(name);
    }

    // Recover the previous match expression
    int slash = match.lastIndexOf('/');
    if (slash >= 0) {
      match = match.substring(0, slash);
    } else {
      match = "";
    }
  }

  /**
   * Return the top object on the stack without removing it. If there are no
   * objects on the stack, return <code>null</code>.
   * 
   * @return the top object on the stack without removing it.
   */
  final Object peek() {
    int size = stack.size();
    return size == 0 ? null : stack.get(size - 1);
  }

  /**
   * Pop the top object off of the stack, and return it. If there are no objects
   * on the stack, return <code>null</code>.
   * 
   * @return the top object off of the stack.
   */
  final Object pop() {
    int size = stack.size();
    return size == 0 ? null : stack.remove(size - 1);
  }

  /**
   * Push a new object onto the top of the object stack.
   * 
   * @param object
   *          The new object
   */
  final void push(final Object object) {
    stack.add(object);
  }

  static final class RuleSet {

    private final HashMap<String, Object> rules = new HashMap<String, Object>();

    private final ArrayList<String> lpatterns = new ArrayList<String>();

    private final ArrayList<String> rpatterns = new ArrayList<String>();

    public void add(final String path, final Object rule) {
      String pattern = path;
      if (path.startsWith("*/")) {
        pattern = path.substring(1);
        lpatterns.add(pattern);
      } else if (path.endsWith("/*")) {
        pattern = path.substring(0, path.length() - 1);
        rpatterns.add(pattern);
      }
      rules.put(pattern, rule);
    }

    public Object match(final String path) {
      if (rules.containsKey(path)) {
        return rules.get(path);
      }

      int n = path.lastIndexOf('/');
      for (Iterator<String> it = lpatterns.iterator(); it.hasNext();) {
        String pattern = it.next();
        if (path.substring(n).endsWith(pattern)) {
          return rules.get(pattern);
        }
      }

      for (Iterator<String> it = rpatterns.iterator(); it.hasNext();) {
        String pattern = it.next();
        if (path.startsWith(pattern)) {
          return rules.get(pattern);
        }
      }

      return null;
    }
  }

  /**
   * Rule
   */
  protected abstract class Rule {

    public void begin(final String name, final Attributes attrs) throws SAXException {
    }

    public void end(final String name) {
    }

    protected final Object getValue(final String desc, final String val) throws SAXException {
      Object value = null;
      if (val != null) {
        if ("Ljava/lang/String;".equals(desc)) {
          value = decode(val);
        } else if ("Ljava/lang/Integer;".equals(desc) || "I".equals(desc) || "S".equals(desc) || "B".equals(desc) || "C".equals(desc)
            || "Z".equals(desc)) {
          value = new Integer(val);

        } else if ("Ljava/lang/Short;".equals(desc)) {
          value = new Short(val);

        } else if ("Ljava/lang/Byte;".equals(desc)) {
          value = new Byte(val);

        } else if ("Ljava/lang/Character;".equals(desc)) {
          value = new Character(decode(val).charAt(0));

        } else if ("Ljava/lang/Boolean;".equals(desc)) {
          value = Boolean.valueOf(val);

        } else if ("Ljava/lang/Long;".equals(desc) || "J".equals(desc)) {
          value = new Long(val);
        } else if ("Ljava/lang/Float;".equals(desc) || "F".equals(desc)) {
          value = new Float(val);
        } else if ("Ljava/lang/Double;".equals(desc) || "D".equals(desc)) {
          value = new Double(val);
        } else if (Type.getDescriptor(Type.class).equals(desc)) {
          value = Type.getType(val);

        } else if (Type.getDescriptor(Handle.class).equals(desc)) {
          value = decodeHandle(val);

        } else {
          // TODO use of default toString().
          throw new SAXException("Invalid value:" + val + " desc:" + desc + " ctx:" + this);
        }
      }
      return value;
    }

    Handle decodeHandle(final String val) throws SAXException {
      try {
        int dotIndex = val.indexOf('.');
        int descIndex = val.indexOf('(', dotIndex + 1);
        int tagIndex = val.lastIndexOf('(');
        int itfIndex = val.indexOf(' ', tagIndex + 1);

        boolean itf = itfIndex != -1;
        int tag = Integer.parseInt(val.substring(tagIndex + 1, itf ? val.length() - 1 : itfIndex));
        String owner = val.substring(0, dotIndex);
        String name = val.substring(dotIndex + 1, descIndex);
        String desc = val.substring(descIndex, tagIndex - 1);
        return new Handle(tag, owner, name, desc, itf);

      } catch (RuntimeException e) {
        throw new SAXException("Malformed handle " + val, e);
      }
    }

    private final String decode(final String val) throws SAXException {
      StringBuilder sb = new StringBuilder(val.length());
      try {
        int n = 0;
        while (n < val.length()) {
          char c = val.charAt(n);
          if (c == '\\') {
            n++;
            c = val.charAt(n);
            if (c == '\\') {
              sb.append('\\');
            } else {
              n++; // skip 'u'
              sb.append((char) Integer.parseInt(val.substring(n, n + 4), 16));
              n += 3;
            }
          } else {
            sb.append(c);
          }
          n++;
        }

      } catch (RuntimeException ex) {
        throw new SAXException(ex);
      }
      return sb.toString();
    }

    protected final Label getLabel(final Object label) {
      Label lbl = labels.get(label);
      if (lbl == null) {
        lbl = new Label();
        labels.put(label, lbl);
      }
      return lbl;
    }

    // TODO verify move to stack
    protected final MethodVisitor getCodeVisitor() {
      return (MethodVisitor) peek();
    }

    protected final int getAccess(final String s) {
      int access = 0;
      if (s.indexOf("public") != -1) {
        access |= ACC_PUBLIC;
      }
      if (s.indexOf("private") != -1) {
        access |= ACC_PRIVATE;
      }
      if (s.indexOf("protected") != -1) {
        access |= ACC_PROTECTED;
      }
      if (s.indexOf("static") != -1) {
        access |= ACC_STATIC;
      }
      if (s.indexOf("final") != -1) {
        access |= ACC_FINAL;
      }
      if (s.indexOf("super") != -1) {
        access |= ACC_SUPER;
      }
      if (s.indexOf("synchronized") != -1) {
        access |= ACC_SYNCHRONIZED;
      }
      if (s.indexOf("volatile") != -1) {
        access |= ACC_VOLATILE;
      }
      if (s.indexOf("bridge") != -1) {
        access |= ACC_BRIDGE;
      }
      if (s.indexOf("varargs") != -1) {
        access |= ACC_VARARGS;
      }
      if (s.indexOf("transient") != -1) {
        access |= ACC_TRANSIENT;
      }
      if (s.indexOf("native") != -1) {
        access |= ACC_NATIVE;
      }
      if (s.indexOf("interface") != -1) {
        access |= ACC_INTERFACE;
      }
      if (s.indexOf("abstract") != -1) {
        access |= ACC_ABSTRACT;
      }
      if (s.indexOf("strict") != -1) {
        access |= ACC_STRICT;
      }
      if (s.indexOf("synthetic") != -1) {
        access |= ACC_SYNTHETIC;
      }
      if (s.indexOf("annotation") != -1) {
        access |= ACC_ANNOTATION;
      }
      if (s.indexOf("enum") != -1) {
        access |= ACC_ENUM;
      }
      if (s.indexOf("deprecated") != -1) {
        access |= ACC_DEPRECATED;
      }
      if (s.indexOf("mandated") != -1) {
        access |= ACC_MANDATED;
      }
      if (s.indexOf("module") != -1) {
        access |= ACC_MODULE;
      }
      if (s.indexOf("open") != -1) {
        access |= ACC_OPEN;
      }
      if (s.indexOf("transitive") != -1) {
        access |= ACC_TRANSITIVE;
      }
      return access;
    }
  }

  /**
   * ClassRule
   */
  final class ClassRule extends Rule {

    @Override
    public final void begin(final String name, final Attributes attrs) {
      int major = Integer.parseInt(attrs.getValue("major"));
      int minor = Integer.parseInt(attrs.getValue("minor"));
      HashMap<String, Object> vals = new HashMap<String, Object>();
      vals.put("version", minor << 16 | major);
      vals.put("access", attrs.getValue("access"));
      vals.put("name", attrs.getValue("name"));
      vals.put("parent", attrs.getValue("parent"));
      vals.put("source", attrs.getValue("source"));
      vals.put("signature", attrs.getValue("signature"));
      vals.put("interfaces", new ArrayList<String>());
      push(vals);
      // values will be extracted in InterfacesRule.end();
    }
  }

  final class SourceRule extends Rule {

    @Override
    public void begin(final String name, final Attributes attrs) {
      String file = attrs.getValue("file");
      String debug = attrs.getValue("debug");
      cv.visitSource(file, debug);
    }
  }

  /**
   * InterfaceRule
   */
  final class InterfaceRule extends Rule {

    @Override
    @SuppressWarnings("unchecked")
    public final void begin(final String name, final Attributes attrs) {
      ((ArrayList<String>) ((HashMap<?, ?>) peek()).get("interfaces")).add(attrs.getValue("name"));
    }
  }

  /**
   * InterfacesRule
   */
  final class InterfacesRule extends Rule {

    @Override
    public final void end(final String element) {
      HashMap<?, ?> vals = (HashMap<?, ?>) pop();
      int version = ((Integer) vals.get("version")).intValue();
      int access = getAccess((String) vals.get("access"));
      String name = (String) vals.get("name");
      String signature = (String) vals.get("signature");
      String parent = (String) vals.get("parent");
      ArrayList<?> infs = (ArrayList<?>) vals.get("interfaces");
      String[] interfaces = infs.toArray(new String[infs.size()]);
      cv.visit(version, access, name, signature, parent, interfaces);
      push(cv);
    }
  }

  /**
   * ModuleRule: module, requires, exports, opens, uses and provides
   */
  final class ModuleRule extends Rule {
    @Override
    public final void begin(final String element, final Attributes attrs) throws SAXException {
      if ("module".equals(element)) {
        push(cv.visitModule(attrs.getValue("name"), getAccess(attrs.getValue("access")), attrs.getValue("version")));
      } else if ("main-class".equals(element)) {
        ModuleVisitor mv = (ModuleVisitor) peek();
        mv.visitMainClass(attrs.getValue("name"));
      } else if ("packages".equals(element)) {
        ModuleVisitor mv = (ModuleVisitor) peek();
        mv.visitPackage(attrs.getValue("name"));
      } else if ("requires".equals(element)) {
        ModuleVisitor mv = (ModuleVisitor) peek();
        int access = getAccess(attrs.getValue("access"));
        if ((access & Opcodes.ACC_STATIC) != 0) {
          access = access & ~Opcodes.ACC_STATIC | Opcodes.ACC_STATIC_PHASE;
        }
        mv.visitRequire(attrs.getValue("module"), access, attrs.getValue("version"));
      } else if ("exports".equals(element)) {
        push(attrs.getValue("name"));
        push(getAccess(attrs.getValue("access")));
        ArrayList<String> list = new ArrayList<String>();
        push(list);
      } else if ("opens".equals(element)) {
        push(attrs.getValue("name"));
        push(getAccess(attrs.getValue("access")));
        ArrayList<String> list = new ArrayList<String>();
        push(list);
      } else if ("to".equals(element)) {
        @SuppressWarnings("unchecked")
        ArrayList<String> list = (ArrayList<String>) peek();
        list.add(attrs.getValue("module"));
      } else if ("uses".equals(element)) {
        ModuleVisitor mv = (ModuleVisitor) peek();
        mv.visitUse(attrs.getValue("service"));
      } else if ("provides".equals(element)) {
        push(attrs.getValue("service"));
        push(0); // see end() below
        ArrayList<String> list = new ArrayList<String>();
        push(list);
      } else if ("with".equals(element)) {
        @SuppressWarnings("unchecked")
        ArrayList<String> list = (ArrayList<String>) peek();
        list.add(attrs.getValue("provider"));
      }
    }

    @Override
    public void end(final String element) {
      boolean exports = "exports".equals(element);
      boolean opens = "opens".equals(element);
      boolean provides = "provides".equals(element);
      if (exports | opens | provides) {
        @SuppressWarnings("unchecked")
        ArrayList<String> list = (ArrayList<String>) pop();
        int access = (Integer) pop();
        String name = (String) pop();
        String[] tos = null;
        if (!list.isEmpty()) {
          tos = list.toArray(new String[list.size()]);
        }
        ModuleVisitor mv = (ModuleVisitor) peek();
        if (exports) {
          mv.visitExport(name, access, tos);
        } else {
          if (opens) {
            mv.visitOpen(name, access, tos);
          } else {
            mv.visitProvide(name, tos);
          }
        }
      } else if ("module".equals(element)) {
        ((ModuleVisitor) pop()).visitEnd();
      }
    }
  }

  /**
   * OuterClassRule
   */
  final class OuterClassRule extends Rule {

    @Override
    public final void begin(final String element, final Attributes attrs) {
      String owner = attrs.getValue("owner");
      String name = attrs.getValue("name");
      String desc = attrs.getValue("desc");
      cv.visitOuterClass(owner, name, desc);
    }
  }

  /**
   * InnerClassRule
   */
  final class InnerClassRule extends Rule {

    @Override
    public final void begin(final String element, final Attributes attrs) {
      int access = getAccess(attrs.getValue("access"));
      String name = attrs.getValue("name");
      String outerName = attrs.getValue("outerName");
      String innerName = attrs.getValue("innerName");
      cv.visitInnerClass(name, outerName, innerName, access);
    }
  }

  /**
   * FieldRule
   */
  final class FieldRule extends Rule {

    @Override
    public final void begin(final String element, final Attributes attrs) throws SAXException {
      int access = getAccess(attrs.getValue("access"));
      String name = attrs.getValue("name");
      String signature = attrs.getValue("signature");
      String desc = attrs.getValue("desc");
      Object value = getValue(desc, attrs.getValue("value"));
      push(cv.visitField(access, name, desc, signature, value));
    }

    @Override
    public void end(final String name) {
      ((FieldVisitor) pop()).visitEnd();
    }
  }

  /**
   * MethodRule
   */
  final class MethodRule extends Rule {

    @Override
    public final void begin(final String name, final Attributes attrs) {
      labels = new HashMap<Object, Label>();
      HashMap<String, Object> vals = new HashMap<String, Object>();
      vals.put("access", attrs.getValue("access"));
      vals.put("name", attrs.getValue("name"));
      vals.put("desc", attrs.getValue("desc"));
      vals.put("signature", attrs.getValue("signature"));
      vals.put("exceptions", new ArrayList<String>());
      push(vals);
      // values will be extracted in ExceptionsRule.end();
    }

    @Override
    public final void end(final String name) {
      ((MethodVisitor) pop()).visitEnd();
      labels = null;
    }
  }

  /**
   * ExceptionRule
   */
  final class ExceptionRule extends Rule {

    @Override
    @SuppressWarnings("unchecked")
    public final void begin(final String name, final Attributes attrs) {
      ((ArrayList<String>) ((HashMap<?, ?>) peek()).get("exceptions")).add(attrs.getValue("name"));
    }
  }

  /**
   * ExceptionsRule
   */
  final class ExceptionsRule extends Rule {

    @Override
    public final void end(final String element) {
      HashMap<?, ?> vals = (HashMap<?, ?>) pop();
      int access = getAccess((String) vals.get("access"));
      String name = (String) vals.get("name");
      String desc = (String) vals.get("desc");
      String signature = (String) vals.get("signature");
      ArrayList<?> excs = (ArrayList<?>) vals.get("exceptions");
      String[] exceptions = excs.toArray(new String[excs.size()]);

      push(cv.visitMethod(access, name, desc, signature, exceptions));
    }
  }

  /**
   * MethodParameterRule
   */
  final class MethodParameterRule extends Rule {
    @Override
    public void begin(final String nm, final Attributes attrs) {
      String name = attrs.getValue("name");
      int access = getAccess(attrs.getValue("access"));
      getCodeVisitor().visitParameter(name, access);
    }
  }

  /**
   * TableSwitchRule
   */
  final class TableSwitchRule extends Rule {

    @Override
    public final void begin(final String name, final Attributes attrs) {
      HashMap<String, Object> vals = new HashMap<String, Object>();
      vals.put("min", attrs.getValue("min"));
      vals.put("max", attrs.getValue("max"));
      vals.put("dflt", attrs.getValue("dflt"));
      vals.put("labels", new ArrayList<String>());
      push(vals);
    }

    @Override
    public final void end(final String name) {
      HashMap<?, ?> vals = (HashMap<?, ?>) pop();
      int min = Integer.parseInt((String) vals.get("min"));
      int max = Integer.parseInt((String) vals.get("max"));
      Label dflt = getLabel(vals.get("dflt"));
      ArrayList<?> lbls = (ArrayList<?>) vals.get("labels");
      Label[] labels = lbls.toArray(new Label[lbls.size()]);
      getCodeVisitor().visitTableSwitchInsn(min, max, dflt, labels);
    }
  }

  /**
   * TableSwitchLabelRule
   */
  final class TableSwitchLabelRule extends Rule {

    @Override
    @SuppressWarnings("unchecked")
    public final void begin(final String name, final Attributes attrs) {
      ((ArrayList<Label>) ((HashMap<?, ?>) peek()).get("labels")).add(getLabel(attrs.getValue("name")));
    }
  }

  /**
   * LookupSwitchRule
   */
  final class LookupSwitchRule extends Rule {

    @Override
    public final void begin(final String name, final Attributes attrs) {
      HashMap<String, Object> vals = new HashMap<String, Object>();
      vals.put("dflt", attrs.getValue("dflt"));
      vals.put("labels", new ArrayList<Label>());
      vals.put("keys", new ArrayList<String>());
      push(vals);
    }

    @Override
    public final void end(final String name) {
      HashMap<?, ?> vals = (HashMap<?, ?>) pop();
      Label dflt = getLabel(vals.get("dflt"));
      @SuppressWarnings("unchecked")
      ArrayList<String> keyList = (ArrayList<String>) vals.get("keys");
      ArrayList<?> lbls = (ArrayList<?>) vals.get("labels");
      Label[] labels = lbls.toArray(new Label[lbls.size()]);
      int[] keys = new int[keyList.size()];
      for (int i = 0; i < keys.length; i++) {
        keys[i] = Integer.parseInt(keyList.get(i));
      }
      getCodeVisitor().visitLookupSwitchInsn(dflt, keys, labels);
    }
  }

  /**
   * LookupSwitchLabelRule
   */
  final class LookupSwitchLabelRule extends Rule {

    @Override
    @SuppressWarnings("unchecked")
    public final void begin(final String name, final Attributes attrs) {
      HashMap<?, ?> vals = (HashMap<?, ?>) peek();
      ((ArrayList<Label>) vals.get("labels")).add(getLabel(attrs.getValue("name")));
      ((ArrayList<String>) vals.get("keys")).add(attrs.getValue("key"));
    }
  }

  /**
   * FrameRule
   */
  final class FrameRule extends Rule {

    @Override
    public void begin(final String name, final Attributes attrs) {
      HashMap<String, Object> typeLists = new HashMap<String, Object>();
      typeLists.put("local", new ArrayList<Object>());
      typeLists.put("stack", new ArrayList<Object>());
      push(attrs.getValue("type"));
      push(attrs.getValue("count") == null ? "0" : attrs.getValue("count"));
      push(typeLists);
    }

    @Override
    public void end(final String name) {
      HashMap<?, ?> typeLists = (HashMap<?, ?>) pop();
      ArrayList<?> locals = (ArrayList<?>) typeLists.get("local");
      int nLocal = locals.size();
      Object[] local = locals.toArray();
      ArrayList<?> stacks = (ArrayList<?>) typeLists.get("stack");
      int nStack = stacks.size();
      Object[] stack = stacks.toArray();
      String count = (String) pop();
      String type = (String) pop();
      if ("NEW".equals(type)) {
        getCodeVisitor().visitFrame(F_NEW, nLocal, local, nStack, stack);
      } else if ("FULL".equals(type)) {
        getCodeVisitor().visitFrame(F_FULL, nLocal, local, nStack, stack);
      } else if ("APPEND".equals(type)) {
        getCodeVisitor().visitFrame(F_APPEND, nLocal, local, 0, null);
      } else if ("CHOP".equals(type)) {
        getCodeVisitor().visitFrame(F_CHOP, Integer.parseInt(count), null, 0, null);
      } else if ("SAME".equals(type)) {
        getCodeVisitor().visitFrame(F_SAME, 0, null, 0, null);
      } else if ("SAME1".equals(type)) {
        getCodeVisitor().visitFrame(F_SAME1, 0, null, nStack, stack);
      }
    }
  }

  final class FrameTypeRule extends Rule {

    @Override
    public void begin(final String name, final Attributes attrs) {
      @SuppressWarnings("unchecked")
      ArrayList<Object> types = (ArrayList<Object>) ((HashMap<?, ?>) peek()).get(name);
      String type = attrs.getValue("type");
      if ("uninitialized".equals(type)) {
        types.add(getLabel(attrs.getValue("label")));
      } else {
        Integer t = TYPES.get(type);
        if (t == null) {
          types.add(type);
        } else {
          types.add(t);
        }
      }
    }
  }

  /**
   * LabelRule
   */
  final class LabelRule extends Rule {

    @Override
    public final void begin(final String name, final Attributes attrs) {
      getCodeVisitor().visitLabel(getLabel(attrs.getValue("name")));
    }
  }

  /**
   * TryCatchRule
   */
  final class TryCatchRule extends Rule {

    @Override
    public final void begin(final String name, final Attributes attrs) {
      Label start = getLabel(attrs.getValue("start"));
      Label end = getLabel(attrs.getValue("end"));
      Label handler = getLabel(attrs.getValue("handler"));
      String type = attrs.getValue("type");
      getCodeVisitor().visitTryCatchBlock(start, end, handler, type);
    }
  }

  /**
   * LineNumberRule
   */
  final class LineNumberRule extends Rule {

    @Override
    public final void begin(final String name, final Attributes attrs) {
      int line = Integer.parseInt(attrs.getValue("line"));
      Label start = getLabel(attrs.getValue("start"));
      getCodeVisitor().visitLineNumber(line, start);
    }
  }

  /**
   * LocalVarRule
   */
  final class LocalVarRule extends Rule {

    @Override
    public final void begin(final String element, final Attributes attrs) {
      String name = attrs.getValue("name");
      String desc = attrs.getValue("desc");
      String signature = attrs.getValue("signature");
      Label start = getLabel(attrs.getValue("start"));
      Label end = getLabel(attrs.getValue("end"));
      int var = Integer.parseInt(attrs.getValue("var"));
      getCodeVisitor().visitLocalVariable(name, desc, signature, start, end, var);
    }
  }

  /**
   * InvokeDynamicRule
   */
  final class InvokeDynamicRule extends Rule {
    @Override
    public final void begin(final String element, final Attributes attrs) throws SAXException {
      push(attrs.getValue("name"));
      push(attrs.getValue("desc"));
      push(decodeHandle(attrs.getValue("bsm")));
      push(new ArrayList<Object>());
    }

    @Override
    public final void end(final String element) {
      ArrayList<?> bsmArgs = (ArrayList<?>) pop();
      Handle bsm = (Handle) pop();
      String desc = (String) pop();
      String name = (String) pop();
      getCodeVisitor().visitInvokeDynamicInsn(name, desc, bsm, bsmArgs.toArray());
    }
  }

  /**
   * InvokeDynamicBsmArgumentsRule
   */
  final class InvokeDynamicBsmArgumentsRule extends Rule {
    @Override
    public final void begin(final String element, final Attributes attrs) throws SAXException {
      @SuppressWarnings("unchecked")
      ArrayList<Object> bsmArgs = (ArrayList<Object>) peek();
      bsmArgs.add(getValue(attrs.getValue("desc"), attrs.getValue("cst")));
    }
  }

  /**
   * OpcodesRule
   */
  final class OpcodesRule extends Rule {

    // public boolean match( String match, String element) {
    // return match.startsWith( path) && OPCODES.containsKey( element);
    // }

    @Override
    public final void begin(final String element, final Attributes attrs) throws SAXException {
      Opcode o = OPCODES.get(element);
      if (o == null) {
        throw new SAXException("Invalid element: " + element + " at " + match);
      }

      switch (o.type) {
      case OpcodeGroup.INSN:
        getCodeVisitor().visitInsn(o.opcode);
        break;

      case OpcodeGroup.INSN_FIELD:
        getCodeVisitor().visitFieldInsn(o.opcode, attrs.getValue("owner"), attrs.getValue("name"), attrs.getValue("desc"));
        break;

      case OpcodeGroup.INSN_INT:
        getCodeVisitor().visitIntInsn(o.opcode, Integer.parseInt(attrs.getValue("value")));
        break;

      case OpcodeGroup.INSN_JUMP:
        getCodeVisitor().visitJumpInsn(o.opcode, getLabel(attrs.getValue("label")));
        break;

      case OpcodeGroup.INSN_METHOD:
        getCodeVisitor().visitMethodInsn(o.opcode, attrs.getValue("owner"), attrs.getValue("name"), attrs.getValue("desc"),
            attrs.getValue("itf").equals("true"));
        break;

      case OpcodeGroup.INSN_TYPE:
        getCodeVisitor().visitTypeInsn(o.opcode, attrs.getValue("desc"));
        break;

      case OpcodeGroup.INSN_VAR:
        getCodeVisitor().visitVarInsn(o.opcode, Integer.parseInt(attrs.getValue("var")));
        break;

      case OpcodeGroup.INSN_IINC:
        getCodeVisitor().visitIincInsn(Integer.parseInt(attrs.getValue("var")), Integer.parseInt(attrs.getValue("inc")));
        break;

      case OpcodeGroup.INSN_LDC:
        getCodeVisitor().visitLdcInsn(getValue(attrs.getValue("desc"), attrs.getValue("cst")));
        break;

      case OpcodeGroup.INSN_MULTIANEWARRAY:
        getCodeVisitor().visitMultiANewArrayInsn(attrs.getValue("desc"), Integer.parseInt(attrs.getValue("dims")));
        break;

      default:
        throw new Error("Internal error");

      }
    }
  }

  /**
   * MaxRule
   */
  final class MaxRule extends Rule {

    @Override
    public final void begin(final String element, final Attributes attrs) {
      int maxStack = Integer.parseInt(attrs.getValue("maxStack"));
      int maxLocals = Integer.parseInt(attrs.getValue("maxLocals"));
      getCodeVisitor().visitMaxs(maxStack, maxLocals);
    }
  }

  final class AnnotationRule extends Rule {

    @Override
    public void begin(final String name, final Attributes attrs) {
      String desc = attrs.getValue("desc");
      boolean visible = Boolean.valueOf(attrs.getValue("visible")).booleanValue();

      Object v = peek();
      if (v instanceof ClassVisitor) {
        push(((ClassVisitor) v).visitAnnotation(desc, visible));
      } else if (v instanceof FieldVisitor) {
        push(((FieldVisitor) v).visitAnnotation(desc, visible));
      } else if (v instanceof MethodVisitor) {
        push(((MethodVisitor) v).visitAnnotation(desc, visible));
      }
    }

    @Override
    public void end(final String name) {
      AnnotationVisitor av = (AnnotationVisitor) pop();
      if (av != null) {
        av.visitEnd();
      }
    }
  }

  final class TypeAnnotationRule extends Rule {

    @Override
    public void begin(final String name, final Attributes attrs) {
      String desc = attrs.getValue("desc");
      boolean visible = Boolean.valueOf(attrs.getValue("visible")).booleanValue();
      int typeRef = Integer.parseInt(attrs.getValue("typeRef"));
      TypePath typePath = TypePath.fromString(attrs.getValue("typePath"));

      Object v = peek();
      if (v instanceof ClassVisitor) {
        push(((ClassVisitor) v).visitTypeAnnotation(typeRef, typePath, desc, visible));
      } else if (v instanceof FieldVisitor) {
        push(((FieldVisitor) v).visitTypeAnnotation(typeRef, typePath, desc, visible));
      } else if (v instanceof MethodVisitor) {
        push(((MethodVisitor) v).visitTypeAnnotation(typeRef, typePath, desc, visible));
      }
    }

    @Override
    public void end(final String name) {
      AnnotationVisitor av = (AnnotationVisitor) pop();
      if (av != null) {
        av.visitEnd();
      }
    }
  }

  final class AnnotationParameterRule extends Rule {

    @Override
    public void begin(final String name, final Attributes attrs) {
      int parameter = Integer.parseInt(attrs.getValue("parameter"));
      String desc = attrs.getValue("desc");
      boolean visible = Boolean.valueOf(attrs.getValue("visible")).booleanValue();

      push(((MethodVisitor) peek()).visitParameterAnnotation(parameter, desc, visible));
    }

    @Override
    public void end(final String name) {
      AnnotationVisitor av = (AnnotationVisitor) pop();
      if (av != null) {
        av.visitEnd();
      }
    }
  }

  final class InsnAnnotationRule extends Rule {

    @Override
    public void begin(final String name, final Attributes attrs) {
      String desc = attrs.getValue("desc");
      boolean visible = Boolean.valueOf(attrs.getValue("visible")).booleanValue();
      int typeRef = Integer.parseInt(attrs.getValue("typeRef"));
      TypePath typePath = TypePath.fromString(attrs.getValue("typePath"));
      push(((MethodVisitor) peek()).visitInsnAnnotation(typeRef, typePath, desc, visible));
    }

    @Override
    public void end(final String name) {
      AnnotationVisitor av = (AnnotationVisitor) pop();
      if (av != null) {
        av.visitEnd();
      }
    }
  }

  final class TryCatchAnnotationRule extends Rule {

    @Override
    public void begin(final String name, final Attributes attrs) {
      String desc = attrs.getValue("desc");
      boolean visible = Boolean.valueOf(attrs.getValue("visible")).booleanValue();
      int typeRef = Integer.parseInt(attrs.getValue("typeRef"));
      TypePath typePath = TypePath.fromString(attrs.getValue("typePath"));
      push(((MethodVisitor) peek()).visitTryCatchAnnotation(typeRef, typePath, desc, visible));
    }

    @Override
    public void end(final String name) {
      AnnotationVisitor av = (AnnotationVisitor) pop();
      if (av != null) {
        av.visitEnd();
      }
    }
  }

  final class LocalVariableAnnotationRule extends Rule {

    @Override
    public void begin(final String name, final Attributes attrs) {
      String desc = attrs.getValue("desc");
      boolean visible = Boolean.valueOf(attrs.getValue("visible")).booleanValue();
      int typeRef = Integer.parseInt(attrs.getValue("typeRef"));
      TypePath typePath = TypePath.fromString(attrs.getValue("typePath"));
      String[] s = attrs.getValue("start").split(" ");
      Label[] start = new Label[s.length];
      for (int i = 0; i < start.length; ++i) {
        start[i] = getLabel(s[i]);
      }
      String[] e = attrs.getValue("end").split(" ");
      Label[] end = new Label[e.length];
      for (int i = 0; i < end.length; ++i) {
        end[i] = getLabel(e[i]);
      }
      String[] v = attrs.getValue("index").split(" ");
      int[] index = new int[v.length];
      for (int i = 0; i < index.length; ++i) {
        index[i] = Integer.parseInt(v[i]);
      }
      push(((MethodVisitor) peek()).visitLocalVariableAnnotation(typeRef, typePath, start, end, index, desc, visible));
    }

    @Override
    public void end(final String name) {
      AnnotationVisitor av = (AnnotationVisitor) pop();
      if (av != null) {
        av.visitEnd();
      }
    }
  }

  final class AnnotationValueRule extends Rule {

    @Override
    public void begin(final String nm, final Attributes attrs) throws SAXException {
      AnnotationVisitor av = (AnnotationVisitor) peek();
      if (av != null) {
        av.visit(attrs.getValue("name"), getValue(attrs.getValue("desc"), attrs.getValue("value")));
      }
    }
  }

  final class AnnotationValueEnumRule extends Rule {

    @Override
    public void begin(final String nm, final Attributes attrs) {
      AnnotationVisitor av = (AnnotationVisitor) peek();
      if (av != null) {
        av.visitEnum(attrs.getValue("name"), attrs.getValue("desc"), attrs.getValue("value"));
      }
    }
  }

  final class AnnotationValueAnnotationRule extends Rule {

    @Override
    public void begin(final String nm, final Attributes attrs) {
      AnnotationVisitor av = (AnnotationVisitor) peek();
      push(av == null ? null : av.visitAnnotation(attrs.getValue("name"), attrs.getValue("desc")));
    }

    @Override
    public void end(final String name) {
      AnnotationVisitor av = (AnnotationVisitor) pop();
      if (av != null) {
        av.visitEnd();
      }
    }
  }

  final class AnnotationValueArrayRule extends Rule {

    @Override
    public void begin(final String nm, final Attributes attrs) {
      AnnotationVisitor av = (AnnotationVisitor) peek();
      push(av == null ? null : av.visitArray(attrs.getValue("name")));
    }

    @Override
    public void end(final String name) {
      AnnotationVisitor av = (AnnotationVisitor) pop();
      if (av != null) {
        av.visitEnd();
      }
    }
  }

  final class AnnotationDefaultRule extends Rule {

    @Override
    public void begin(final String nm, final Attributes attrs) {
      MethodVisitor av = (MethodVisitor) peek();
      push(av == null ? null : av.visitAnnotationDefault());
    }

    @Override
    public void end(final String name) {
      AnnotationVisitor av = (AnnotationVisitor) pop();
      if (av != null) {
        av.visitEnd();
      }
    }
  }

  /**
   * Opcode
   */
  static final class Opcode {

    public final int opcode;

    public final int type;

    Opcode(final int opcode, final int type) {
      this.opcode = opcode;
      this.type = type;
    }
  }
}
